Really Slow Vibrato Possibility?

[bifbangpow]

Hi. I'm May. New here.  Anyhow, I just recently started building pedals.  I've built about 4 now.  Just starting on etching my own boards now.  Anyhow, I would like to build a vibrato pedal (not tremolo, specifically modulation in pitch rather than tone) that has the ability to go extra slow.  I found a pcb for the TryVibe.  So I could buy that and modulate it in some way... or I etch my own board.  But I dont know enough to know how to control the speed range on the vibrato waves.  Any suggestions on how to do this?

Thanks!

May
http://maymcdonoughandcompany.com

keep on keep on.

[antonis]

You may start by tweaking the Rate and Depth pots...

If you aren't satisfied of the slowest posistion of the  Rate pot (500k C) you may change the 820k resistor or/and the value of the 10μF eletrolyte caps
(you may also tweak the delay chip but you'll have to study enough the tech specs..)


I'll suggest you to add an LED indicator for rate (and for fancy, too.. )

http://www.runoffgroove.com/tri-vibe.html

[PRR]

Slow vibrato (pitch) requires a LOT of memory. Getting enough phase-shift stages together would be a beast. This is best done on tape or in digital.

[Mark Hammer]

Typically, pitch shift is imperceptible if too slow, or too modest.  If one has a phase shifter with a 500k rate pot, and you want to make it do vibrato, best to drop that pot down to 50k, because rates slower than maybe 1hz will be very hard to detect.

Alternatively, the pitch change would need to be substantial; on the order of a tone and a half or more for slow change to be audible.